In the related art, there is a known technology for extracting a characteristic spectrum of skin conditions and so forth by using a 16-band multispectral camera (for example, see Patent Literature 1). With this technology, it is possible to ascertain subtle color changes that are difficult to distinguish with the human eye.
Specifically, with the technology in Patent Literature 1, image acquisition of a wide-band image and a narrow-band image is performed using a digital camera for RGB color image acquisition. In this case, although an RGB image can be readily obtained, for a narrow-band image, the image acquisition takes time because illumination light of different colors is radiated sequentially. Thus, when acquiring an image of a moving subject, the shape of the subject changes between the RGB image and the narrow-band image, or between narrow-band images.